Integrating Runtime Verification into an
Automated UAS Traffic Management System

Matthew Cauwels, Abigail Hammer, Benjamin Hertz, Phillip H. Jones, Kristin Y. Rozier

This webpage contains supplementary specifications for "Integrating Runtime Verification into an
Automated UAS Traffic Management System" by M. Cauwels, A. Hammer, B. Hertz, P. H. Jones, and K. Y. Rozier

OR_UTM_5

Specification Description

All longitude (fpLon) waypoints of any UAS's telemetry data will be bounded between LonLB and LonUB.

Signals Required

fpLon

Boolean Conversion of Signals to Atomic Inputs 

fpLon_leq_LonUB = 1;
for(i = 0; i < NumUAS; i++)
{
    // if UAS i's fpLon is greater than the upper bounded
    // and the value is not "nan"
    for(j = 0; j < NumWps[i]; j++)
    {
        if((fpLon[i,j] > LonUB) && (fpLon[i,j] == fpLon[i,j])
        { 
            fpLon_leq_LonUB = 0;
        }
    }
}                       
fpLon_geq_LonLB = 1;
for(i = 0; i < NumUAS; i++)
{
    // if UAS i's fpLon is less than the lower bounded
    // and the value is not "nan"
    for(j = 0; j < NumWps[i]; j++)
    {
        if((fpLon[i,j] < LonLB) && (fpLon[i,j] == fpLon[i,j])
        { 
            fpLon_geq_LonLB = 0;
        }
    }
}

MLTL Specification

Original: fpLon_leq_LonLB ∧ fpLon_geq_LonLB

Fault Explanation

Any waypoint from the flight plan should be within the UTM's airspace

Additional Notes

Figures

Figure 1: All of the flight plan's longitude waypoints (fpLon) from each GCS the UTM reads from the waypoint flight plan datatable.
Figure 2: The output of R2U2's monitoring of specification OR_UTM_5, confirming that no UAS exceeds its operating range.
Figure 3: Since Fig. 1 had no flight plans where fpLon exceeds LonLB or LonUB, we manually injected a fault into a single flight plan's waypoint (purple).
Figure 4: The output of R2U2's monitoring of specification OR_UTM_5, showing that R2U2 catches when the injected fault occurs.